Curcuma longa (turmeric) is an herb which is the major component of two Chinese combination medicines, Jieyu-wan and Xiaoyao-san. These combinations help manage stress and depression. Curcumin is the active component of Curcuma longa. The authors propose to demonstrate that curcumin relieves stress-induced depressive behavior, improves stress-induced hypothalamic-pituitary-adrenal axis (HPA) dysfunction and improves gene changes which are seen in altered HPA dysfunction.
Rats were exposed to 20 days of stress. This resulted in altered behavior, abnormal adrenal gland weight/body weight, increased thickness of the adrenal cortex, increased corticosterone levels and reduced glucocorticoid receptors in the hippocampus. (Levels of corticosterone in rats and levels of cortisol in humans are hallmarks of stress.) These changes indicate altered HPA function. Chronic administration of 5 to 10 mg./kg. curcumin reversed these changes from stress in rats. Reduced body weight was not altered by curcumin treatment.
Stress induced decreases in brain-derived neurotrophic factor (BDNF) protein and other factors. Reduced BDNF is associated with memory impairment as seen with chronic depression. These decreases were relieved by administration of curcumin in the above doses. Curcumin protects from stress-induced hippocampal and frontal brain cell damage. (CREB is a portion of the BDNF protein.)
CONCLUSION: Curcumin effects in chronically stressed animals and humans may work by improving the HPA axis and increasing brain-derived neurotrophic factor (BDNF.) Curcumin was shown to relieve the many effects of chronic stress in rats, including the downregulation of certain RNA genes. The neurobiology of stress in rats seems to be closely related to the neurobiology of stress in humans.
NOTE: Chronic, unpredictable stress in humans is seen as a cause of depression. Memory impairment and loss of brain cells is seen with chronic depression. Studies need to be done to see if curcumin can be of benefit in relieving these problems in humans. There does seem to be good evidence that the biology of stress in rats is similar to that in humans.
Read how the phytosome form of curcumin has improved bioavailability.
The Xaioyao-wan tablets and Xaiyao-san tincture which Rainbow Grocery carries do not contain Curcuma longa.
To read the author’s abstract of the article click on the NCBI link above.